Answer:
Option A
Explanation:
NH4Cl △→ NH3+HCl
A(colourless) B & C ( equimolar quantities)
NH3+HCl→NH4Cl
B dense white fumes
NH3+2K2[HgI4]+3KOH→H2NHgO.HgI+7KI+H2O
Nessler's reagent Brown ppt. Iodine of Milinon's base
HCl+MNO3→MCl+HNO3
C white ppt.
(M= Ag+, Pb2+, Hg+)